Production of corrected colorselection positives for color photography and multicolor printing



y '9, 1935. 0. VAN STRAATEN 2,007,316 PRODUCTION OF CORRECTED COLOR SELECTION POSITIVES FOR COLOR PHOTOGRAPHY AND MULTICOLOR PRINTING Filed June 11, 1934 (9 9 I llI|l||llllllllllmlfllllfllh Illllllllllllllllllllllllme I5 ,4 IlllllllllllllllIlllllllllll' llllllllllllllllllIllllllll p a n in.

7.3 lllllllllllllllllmlllllllflllll 20N|l|llll| Lows OscAR VAN STRAATEN oscmsm By SARA JACOBA VAN STR A TE/V BMW AGELINK VAN RENTERGEM 'EXEcuTR/X By M @b vwweZr/ke ATTORNEY Patented July 9, 1935 t n t it UNITED STATES PATENT} OFFICE PRODUCTION OF CORRECTED COLOR- SELECTION POSITIVES FOR COLOR PHOTOGRAPHY AND MULTICOLOR PRINTING Louis Oscar van Straaten, deceased, lateof Biggekerke, Netherlands, by Sara Jacoba van Straaten, born Agelink van Rentergem, executrix, Biggekerke, Netherlands I Application June 11, 1934, Serial No. 730,138

In the Netherlands June 24, 1933 4 Claims. (Cl. 95-2) This invention relates to aprocess for the pronegative. They merely have the respective shadduction of corrected color-selected positives for ings or tone values corresponding to those promulti-color prints, colored prints on transparent duced byblue, yellow, and red rays, respectively. material, glass, lantern slides and the like. The invention consists in a process for pro- 5 In the production of clichs for these purducing clichs for multicolor prints, colored 5 poses, it is known to produce two, three or more prints on transparent material, lantern slides negatives, with the aid of three color filters (e. g. and the like consisting of producing two, three or green, violet and orangeiwhilst at the same time more photographic negatives of an object with and on ,the same negatives a scale of primary 9. scale of primary colors by employing a numcolors, e. g. blue, yellow and red is produced. ber of different color filters, for example, green 10 This strip with the primary colors serves '-for violet and orange, whereby a scale of primary judging whether the correct shade is obtained. colors for example blue, yellow and red, is re- This method is used in the process according to produced at the same time as the subject of the t e present invention, but in conjunction with a picture, wherein the correctionof the negative new method which will be described in the fOlIOW- red plate obtained with the aid of a green filter 15 i g and Which achieves the Object that at t e is obtained by chromating a negative blue plate end of the vari u t es in t e D I the eand shading it ofi by means of the diapositive quired g mp corrected P1161165 for F obtained from a yellow plate negative and after color printitng are produced withoiit the necessity correctly Shading ofi making a diapositive from g; re i g' g fi g said blue plate, whereupon said diapositive is 20 P me 0 q ng me used for shading off a negative red plate and scribed 111 the specification of Brit. Patent No. making a completely corrected diapositive red 353,151'retouch1ng to a greater or smaller extent plate from said negative fed plate.

is always necessary. It is found in practice that the orange filters The invention will be hereinafter more partic- 25 ularly described with reference to the accompanyavailable are nearly correct, that is absorb practically all the blue rays from ordinary daylight mg drawin allowing all the red and yellow rays to act upon In the following description the Variou Stages the plate which when developed is called the of the process will first be described without any blue plate, whereby the diapositive- (28) made reference being made to the reasons why the va- 30 from the latter s a sufiiciently correct Shading rlous stages are necessary. An explanation of the corresponding t e b u ay The Other filters, reasons for the various stages in the process will i. e., the violet and green filters always have a then 11 general incorrectness, although filters from For the sake of clearness the following table, ferent sources may have it in different degreegiving the significance of the different reference This general incorrectness takes the form of numbers is inc1uded allowing rays which should be absorbed to pass, for example, all green filters which should ab- |=T1g111a1mde1 sorb all the yellow rays and allow all the blue =F filter rays to pass, actually pass some of the yellow i f filger rays which produces an incorrect shading of the fgigg g i i blue plate plate which the present invention eliminates. GISeCOHd gnegaltive blue plate Similarly'all green filters fail to absorb all of the 1;negafive yellow plate red rays. The present invention teaches a novel a=first negative red plate I 45 general procedure for correcting-these general sitsecond negative red plate, defects of violet and green filters and it is within mzchmmated negative second blue plate the skill of the expert in this art to apply the de- |:diapositive f negative yellow m t gree of correction necessary for any particular z= h at d negative yellow plate filters being used, once the general procedure |3= hromated first negativered plate 50 h re taught a been grasped. l4=chromated second negative red plate It is to be understood that the plates shown Il=diapositive of second chromated blue plate hatched in the drawing and herein referred to shaded off as the blue, yellow, and red plates are not ac- 20=negative l4 again gelatinated and chromated 5 tually so colored. but are black like an ordinary 25=diapositive of 20 28=corrected diapositive of first negative blue plate 29=corrected diapositive of first red plate 30=corrected diapositive of negative yellow plate.

The process consists first in taking five photographs of the original with the employment of color filters i. e. an orange filter with which two photographs are taken for producing blue plates, a violet filter with which one photograph is taken for producing a yellow plate and a green filter with which two photographs are taken for producing red plates.

For simplicity, the expressions blue plate, yellow plate and red plate are used throughout the description where a negative, on which the complementary colors of blue, yellow or red have acted to a certain degree, is intended.

In most cases it is not necessary to correct the blue plate 5. In any event the correction is always very slight, so that in practice this plate is not corrected and the necessary diapositive 28 is made directly therefrom. The green filter 4 for producing the red plates must be of such a quality, that it allows the yellow rays from the original to pass completely. The consequence thereof is, however, that the blue rays act less intensively on the plate.

The correction of the red plate 8 is effected in the following manner. Before using the blue plate 6 for correction of the blue in the red plate 8, a diapositive II of the yellow plate 1 is first made, the latter being obtained with the aid of the violet filter 3 as already mentioned; this diapositive ll represents about as much red as ,yellow, viz. the complementary colors of blue.

This diapositive II is now placed on the negative blue plate I, which has previously been chromated and is then exposed to the light. The

blue plate in will then, after being washed out and treated with an anilin coloring material of a color which corresponds as 'much as possible to the color of the clich, be shaded off at those places where red, yellow and. black are represented. The treatment comprising the bringing into contact of a chromated negative with a diapositive, the exposure, the washing out and the treatv ment with anilin coloring material will hereinafter be called shading off.

From the blue plate I! obtained a diapositive I1 is now made, which when employed as the diapositive with the reference number I! will completely correct the red plate ii, i. e. it will remove all blue without a'fiecting the intermediate colors violet, green and black. The result is that the negative i3 is obtained from which the corrected red diapositive 29 may be obtained.

The yellow plate 1 is corrected in the following manner. In practice the complementary colors for eifecting the correction of the yellow plate, consisting of red and blue are not, as was the case with the blue plate, present in one single blue plate or in one single red plate. For the correction of the yellow plate a blue plate and a red plate are therefore necessary. For this purpose one of the red plates (in the drawing red plate 9) after being chromated whereby it forms the red plate I4, is shaded off with the diapositive I! which has already been used as the diapositive for effecting the correction of the red plate l3;

it is then exposed and. after being washed out is treated with an anilin coloring material, so that this red plate H has obtained a shading off of the blue, gray and black in the red plate H. The

red plate 14 is again provided with a chromated gelatin layer and is then, in the form of the negative 20, shaded of! by the existing diapositive ll of the negative yellow plate I, and after having been exposed and washed out the plate is treated with anilin coloring material. From the negative 20 hereby obtained a diapositive 25 is made. This diapositive 25 is shaded off with the negative yellow plate l2, which has previously been chromated. This combination, after being exposed and washed out, is treated with an anilin coloring material and then constitutes the completely corrected yellow plate l2, from which the corrected diapositive 30 is made.

An explanation will now be given of the reasons why the various stages are necessary.

The blue plate obtained with the aid of the orange filter 2 is in practice sufliciently correct for. direct use, so that no correction or only a very slight correction may be necessary; the blue plate 5 is therefore directly used for making the diapositive 28.

The red plate 8 obtained with the aid of the green filter 4 not only contains an image of the red in the original, but also an image in half intensity of the blue in the original. In order to eliminate the undesired blue from the red plate 8, a diapositive i I is made from the yellow plate 1, which latter is obtained with the aid of the violet filter 3. This diapositive II contains in practice red and yellow, the complementary color of blue, in about the same intensity. The diapositive I lis now shaded ofi with the blue plate In, so that the combination ll--lll is obtained. By doing so the blue plate I0 is shaded off at the places where the colors red, yellow, gray and black are represented. With the aid of the negative blue plate in thus obtained the diapositive I1 is made, and this diapositive I l is used for shading off the negative red plate I3, so that the combination ||l3 is obtained, whereby the shading off again takes place. From the negative red plate l3 thus obtained the blue has disappeared, without aiiecting the parts which contain violet, gray and black. This negative red plate I3 can therefore be used directly for making the corrected red diapositive 29.

For effecting the correction of the yellow plate which in practice contains as much red as yellow, the red plate i4 is used. This plate is shaded oil? by the diapositive II which has already been obtained during the correction of the red plate. With this combination the parts which contain blue, gray and black will be shaded off more or less. The negative H thus obtained is now provided with a chromated gelatin layer, so that the negative 20 is formed and this negative is shaded 011 by the diapositive II. The combination ll20 is thus formed and the yellow, blue, gray and black will be shaded off.

From this negative 20 a diapositive 25 is made and the latter is used for shading off the original yellow plate l2. This plate [2 eliminates the red without affecting yellow, gray and black. The diapositive made from the plate i2 is the completely corrected yellow plate 30.

What is claimed is:-

1. Process for producing clichs for multicolor prints, colored prints on transparent material, lantern slides and the like consisting of producing a plurality of photographic negatives of an object with a scale of primary colors by employing a number of different color filters whereby a scale of primary colors is reproduced at the same time as the subject of the picture, correcting a negative red plate, obtained with the aid of a green filter, by chromating a negative blue plate, shading it off by means of a diapositive obtained from a negative yellow plate and after correctly shading ofi making a diapositive from said blue plate, using said last recited diapositive for shading oil a negative red plate, and making a completely corrected diapositive red plate from said negativered plate.

2. Process for producing, clichs for multicolor prints, colored prints on transparent material, lantern slides and the like consisting of producing a plurality of photographic negatives of an object with a scale of primary colors by employing a number of different color filters whereby a scale of primary colors is reproduced at the same time as the subject of the picture, correcting a negative yellow plate by shading off a negative red plate by means of a blue diapositive, sensitizing this red negative again by means of a chromated gelatin film and thereupon shading oil the red plate thus obtained by means of a yellow diapositive, making a diapositive from the shaded oil red negative, using said last recited diapositive for shadingv oil the negative yellow plate, and making a completely corrected yellow diapositive from the said corrected negative yellow plate.

3. Process for producing clichs for multicolor prints, colored prints on transparent material, lantern slides and the like consisting of producing a plurality of photographic negatives of an object with a scale of primary colors by employing a number of different color filters whereby a scale of primary colors is reproduced at the same time as the subject of the picture, correct- .ing a negative red plate, obtained with the aid of a green filter, by chromating a negative blue plate and shading it off by means of a diapositive obtained from a negative yellow plate and after correctly shading ofi making a diapositive from said blue plate, using said lastreciteddiapositive for shading off a negative red plate and making a completely corrected diapositive red plate from said negative red plate and effecting the correction of a negative yellow plate by shading ofi a negative red plate by means of a blue diapositive, sensitizing said last recited red negative by means of a chromated gelatin film and thereupon shading off the red plate thus obtained by means of a yellow diapositive, making a diapositive from the thus obtained red negative, using the same for shading off the negative yellow plate, and making a completely corrected yellow diapositive from the said last recited negative yellow plate.

4. A process for producing clichs for blue, red and yellow colored prints comprising producing a plurality of blue, yellow and red negatives with the aid of orange, violet and green filters, respectively, making a blue diapositive irom a blue negative, chromating a blue negative, forming a yellow diapositive, shading oif said chromated blue negative with said yellow diapositive forming a corrected blue diapositive from said treated chromated blue negative chromating a red negative, shading off the chromated red negative with the corrected blue diapositive, forming a corrected red diapositive from said shaded'ofl. chromated red negative, producing a second shaded off chromated red negative, sensitizing the same, shading off, said sensitized red negative with a yellow diapositive, forming a double corrected red diapositive, chromating a yellow negative, shading ofi said chromated yellow negative with said double corrected red diapositive, and forming a corrected yellow diapositive.

SARA JACOBA VAN STRAATEN,

BORN AGELINK VAN RENTERGEM. Ezecutfizc of the Estate of Louis Oscar van Straaten, Deceased. 

